Over the years, a variety of nasal dilators, nose braces, nasal strips, bandages, breathing equipment, jaw retainers, orthodontic inserts, tongue retainers, mechanisms, instruments and other devices have been suggested to improve breathing quality and have met with varying degrees of success. Devices that require insertion into the nostrils have been tried, with the intent of opening the nostrils and allow more air to enter the nose. Various nasal strips have also been suggested. In one version of the Breathe Right® nasal strip manufactured by CNS, Inc. of Minneapolis, Minn., adhesive strips are lined with two parallel plastic rods. When placed across the bridge of the nose, an adhesive nasal strip adheres to the soft area above the flare of each nostril and provides an excessive pulling force to lift and open the nasal passages. In another version of the Breathe Right® nasal strip, a flexible metal strip is attached to an adhesive band that is placed on the inside of the nose. The spring action of the metal strip pulls the sides of the nose outward. Many other devices have been proposed with the intent of increasing air flow through the nose.
Another approach, analogous to resistance weight training, or high-altitude training, is to practice breathing through artificially high resistance, thereby potentially increasing the strength of various muscles involved in breathing. In other words, rather than making breathing easier by increasing air flow through the nose, this approach makes breathing more difficult during training sessions, hopefully making breathing easier during normal conditions. There are numerous inspiratory resistance trainers that are currently marketed, but these devices require oral inhalation by users. Such devices may indeed increase the strength of various muscles involved in breathing, as advertised, but oral inhalation is generally disfavored by the medical community, and these devices may train users to revert to oral breathing when breathing is difficult, which can be deleterious for users.
Asthma is a chronic respiratory disease afflicting an increasingly large number of individuals. There is no known cure, and treatments are aimed at controlling symptoms and complications. While pharmacotherapy is widely used to treat asthma, many patients seek additional or alternative non-pharmaceutical therapies.
One such therapy utilizes the so-called Buteyko breathing technique. Asthma is often correlated with frequent hyperventilation and low levels of carbon dioxide in the bloodstream. High carbon dioxide levels act on the airway smooth muscle tissue to cause bronchodilation. Proponents of the Buteyko approach believe that asthma can be effectively managed by breathing reduced air volumes. This practice will increase the carbon dioxide level in the bloodstream, purportedly leading to an increase in the body's carbon dioxide setpoint, and therefore allowing higher levels of carbon dioxide to accumulate in the body before initiation of respiration.
In U.S. Patent Application No. 20040255939, Feldman describes a method of increasing the carbon dioxide level in a patient by administering to the patient an inhalant that comprises a mixture of carbon dioxide and atmospheric air. The method can be used to treat a patient suffering from asthma, allergies, muscle tension, pain, insomnia, and/or mental stress, and is described as being faster than the Buteyko breathing technique.
Nasal breathing, particularly nasal inhalation, is widely believed to be preferred to oral breathing, particularly for asthmatics, as nasal inhalation humidifies, warms, and filters incoming air. Bishop et al. (Physiotherapy 93 (2007) 129-136) have recently demonstrated that forced nasal breathing, via mouth taping, has the effect of increasing end-tidal carbon dioxide levels.
Scientific evidence has shown that paced breathing can lower blood pressure significantly by relaxing the muscles surrounding constricted blood vessels. The problem for many people, however, is that proper paced breathing requires years of training and individualized coaching. Typically, it requires some effort to consciously reduce breathing rate. A tonal-based biofeedback system has been incorporated into a portable electronic device (RESPeRATE®, produced by InterCure, Inc.) to lower blood pressure naturally by using biofeedback tones to direct breathing and reduce breathing rate. This FDA-approved device has been clinically demonstrated to reduce blood pressure. It also requires the user to wear a chest strap that monitors breathing, and retails for several hundred dollars.